:root {
  --font: "Be Vietnam Pro", Arial, sans-serif;
  --title: "Baloo 2", "Be Vietnam Pro", sans-serif;
  --tw: 40px;
  --th: 48px;
}
* {
  box-sizing: border-box;
}
[hidden] {
  display: none !important;
}
html,
body {
  margin: 0;
  min-height: 100%;
}
body {
  min-height: 100vh;
  background: radial-gradient(ellipse at 50% 0%, #1e3a7a, #0f1c45 50%, #070d24);
  color: #e6ecff;
  font-family: var(--font);
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  -webkit-user-select: none;
}
button {
  font-family: var(--font);
  color: inherit;
  cursor: pointer;
}
.back {
  position: fixed;
  top: 10px;
  left: 14px;
  z-index: 5;
  color: #9fb0e0;
  font-weight: 600;
  font-size: 13px;
  text-decoration: none;
}

.app {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 10px 8px 14px;
}

/* ---------- Thẻ chỉ số ---------- */
.stats {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}
.stat {
  min-width: 72px;
  padding: 6px 14px 4px;
  border: 1px solid rgba(160, 185, 255, 0.25);
  border-radius: 12px;
  background: rgba(30, 45, 95, 0.75);
  text-align: center;
}
.stat small {
  display: block;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: #9fb0e0;
}
.stat b {
  display: block;
  font: 800 28px/1.15 var(--title);
}
.stat.mode b {
  font: 700 14px/2.4 var(--font);
  color: #ffb86b;
  white-space: nowrap;
}
.c-blue {
  color: #4cc4ff;
}
.c-purple {
  color: #b48cff;
}
.c-yellow {
  color: #ffd23f;
}
.c-green {
  color: #52e3a4;
}
.bump {
  animation: bump 0.35s ease;
}
@keyframes bump {
  40% {
    transform: scale(1.25);
  }
}

/* ---------- Thanh thời gian ---------- */
.timebar {
  width: min(560px, 92vw);
  height: 8px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.12);
  overflow: hidden;
}
.timebar i {
  display: block;
  height: 100%;
  border-radius: 4px;
  background: #3ddc84;
  transition:
    width 0.25s linear,
    background 0.4s;
}
.timebar i.warn {
  background: #ffc531;
}
.timebar i.danger {
  background: #ff4d4d;
}

/* ---------- Bàn ---------- */
.board-wrap {
  position: relative;
}
.board {
  position: relative;
}
/* tạm dừng thì giấu bàn, không cho nhìn trước nước đi khi đồng hồ đứng */
.board-wrap.paused .board {
  visibility: hidden;
}
.tile {
  position: absolute;
  width: var(--tw);
  height: var(--th);
  display: grid;
  place-items: center;
  padding: 0;
  border: 0;
  border-radius: 5px;
  background: linear-gradient(160deg, #fffaf0, #fde2c4 60%, #f6caa0);
  box-shadow:
    inset 0 0 0 1px #fff3e0,
    inset -3px -3px 0 #d9965d,
    inset 3px 3px 0 #fffdf6,
    0 2px 2px rgba(0, 0, 0, 0.35);
  font-size: calc(var(--tw) * 0.68);
  line-height: 1;
  transition:
    left 0.22s ease,
    top 0.22s ease,
    transform 0.15s,
    opacity 0.2s;
}
.tile img {
  width: 84%;
  height: 84%;
  object-fit: contain;
  pointer-events: none;
  -webkit-user-drag: none;
}
/* bộ hình gốc đã có sẵn khung ô kem → hình phủ kín ô, bỏ khung tự vẽ */
.tile.pic {
  background: none;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.45);
  border-radius: 2px;
  overflow: hidden;
}
.tile.pic img {
  width: 100%;
  height: 100%;
  object-fit: fill;
  image-rendering: pixelated;
}
.tile.pic.sel {
  filter: brightness(0.55);
}
.tile span {
  pointer-events: none;
  filter: drop-shadow(0 1px 0 rgba(0, 0, 0, 0.15));
}
.tile:hover {
  filter: brightness(1.05);
}
.tile.sel {
  filter: brightness(0.62);
  transform: translateY(1px);
}
/* gợi ý: viền hồng đậm nằm ngoài ô (không phủ lên hình) + nảy nhẹ,
   nổi rõ trên cả nền xanh lẫn các ô kem bên cạnh */
.tile.hint,
.tile.pic.hint {
  z-index: 2;
  filter: none;
  box-shadow:
    0 0 0 2px #fff,
    0 0 0 5px #ff2e88,
    0 0 14px 5px rgba(255, 46, 136, 0.6);
  animation: hint 0.7s ease-in-out infinite alternate;
}
@keyframes hint {
  from {
    transform: translateY(0) scale(1);
  }
  to {
    transform: translateY(-3px) scale(1.08);
  }
}
@media (prefers-reduced-motion: reduce) {
  .tile.hint {
    animation: none;
  }
}
.tile.bad {
  animation: shake 0.3s;
}
@keyframes shake {
  25% {
    transform: translateX(-3px);
  }
  75% {
    transform: translateX(3px);
  }
}
.tile.gone {
  opacity: 0;
  transform: scale(0.4);
  pointer-events: none;
}
.link {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
  pointer-events: none;
  z-index: 3;
}
.link polyline {
  fill: none;
  stroke: #ff3b3b;
  stroke-width: 4;
  stroke-linecap: round;
  stroke-linejoin: round;
  filter: drop-shadow(0 0 4px #ffde59);
}

.toast {
  position: absolute;
  left: 50%;
  top: 50%;
  z-index: 6;
  padding: 10px 22px;
  border-radius: 12px;
  background: rgba(10, 20, 55, 0.92);
  border: 1px solid rgba(160, 185, 255, 0.35);
  font: 800 22px var(--title);
  color: #ffd23f;
  text-align: center;
  white-space: nowrap;
  transform: translate(-50%, -50%);
  animation: toast 1.6s ease forwards;
  pointer-events: none;
}
.toast small {
  display: block;
  font: 600 14px var(--font);
  color: #cfe0ff;
}
@keyframes toast {
  0% {
    opacity: 0;
    transform: translate(-50%, -40%) scale(0.85);
  }
  15%,
  75% {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
  }
  100% {
    opacity: 0;
  }
}

/* ---------- Hộp thoại ---------- */
.modal {
  position: fixed;
  inset: 0;
  z-index: 20;
  display: grid;
  place-items: center;
  padding: 16px;
  background: rgba(3, 8, 25, 0.55);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}
.card {
  width: min(440px, 100%);
  padding: 22px 24px 20px;
  border: 1px solid rgba(160, 185, 255, 0.3);
  border-radius: 18px;
  background: linear-gradient(180deg, #1c3462, #121f44);
  text-align: center;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
  animation: pop 0.3s cubic-bezier(0.3, 1.5, 0.5, 1);
}
@keyframes pop {
  from {
    transform: scale(0.8);
    opacity: 0;
  }
}
.m-ico {
  font-size: 42px;
  line-height: 1;
}
.card h2 {
  margin: 6px 0;
  font: 800 30px var(--title);
  color: #ffd23f;
}
.card p {
  margin: 0 0 16px;
  color: #cfdaf7;
  line-height: 1.55;
}
.m-btns {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}
.btn {
  min-width: 96px;
  height: 44px;
  padding: 0 18px;
  border: 1px solid rgba(160, 185, 255, 0.35);
  border-radius: 12px;
  background: rgba(40, 60, 115, 0.9);
  font-weight: 700;
  font-size: 15px;
}
.btn.primary {
  border-color: #ffcf3a;
  background: linear-gradient(#ffd84d, #f5b50b);
  color: #3a2600;
  box-shadow: 0 4px 16px rgba(255, 200, 40, 0.35);
}
.btn.on {
  border-color: #ffd23f;
  color: #ffd23f;
}

/* ---------- Nút dưới ---------- */
.tools {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}
.tool {
  position: relative;
  display: flex;
  align-items: center;
  gap: 8px;
  height: 44px;
  padding: 0 16px;
  border: 1px solid rgba(160, 185, 255, 0.28);
  border-radius: 12px;
  background: rgba(30, 45, 95, 0.8);
  font-weight: 700;
  font-size: 14px;
}
.tool:hover {
  background: rgba(45, 65, 125, 0.9);
}
.tool:disabled {
  opacity: 0.4;
  cursor: default;
}
.tool span {
  font-size: 16px;
}
.tool.hint {
  border-color: #ffcf3a;
  background: linear-gradient(#ffd84d, #f5b50b);
  color: #3a2600;
}
.tool.hint i {
  position: absolute;
  top: -8px;
  right: -8px;
  min-width: 20px;
  height: 20px;
  padding: 0 5px;
  border-radius: 10px;
  background: #ff3b3b;
  color: #fff;
  font: 700 12px/20px var(--font);
  font-style: normal;
}

@media (max-width: 640px) {
  .stats {
    gap: 6px;
  }
  .stat {
    min-width: 0;
    padding: 4px 9px 2px;
  }
  .stat small {
    font-size: 9px;
  }
  .stat b {
    font-size: 21px;
  }
  .stat.mode b {
    font-size: 11px;
    line-height: 2.3;
  }
  .tools {
    gap: 6px;
  }
  .tool {
    height: 40px;
    padding: 0 10px;
    font-size: 12px;
    gap: 5px;
  }
  .back {
    position: static;
    align-self: flex-start;
  }
}